diff --git a/cmd/xgo/runtime_gen/core/version.go b/cmd/xgo/runtime_gen/core/version.go
index a4d3a5e7..2febb1fc 100755
--- a/cmd/xgo/runtime_gen/core/version.go
+++ b/cmd/xgo/runtime_gen/core/version.go
@@ -7,8 +7,8 @@ import (
 )
 
 const VERSION = "1.0.39"
-const REVISION = "55af407f826d020bcd28c51663d0879f8d1ca76e+1"
-const NUMBER = 258
+const REVISION = "4d63b2ed7ce161f17d1c311a9b536e82a01769f0+1"
+const NUMBER = 259
 
 // these fields will be filled by compiler
 const XGO_VERSION = ""
diff --git a/cmd/xgo/version.go b/cmd/xgo/version.go
index 0e926faf..00bb464a 100644
--- a/cmd/xgo/version.go
+++ b/cmd/xgo/version.go
@@ -3,8 +3,8 @@ package main
 import "fmt"
 
 const VERSION = "1.0.39"
-const REVISION = "55af407f826d020bcd28c51663d0879f8d1ca76e+1"
-const NUMBER = 258
+const REVISION = "4d63b2ed7ce161f17d1c311a9b536e82a01769f0+1"
+const NUMBER = 259
 
 func getRevision() string {
 	revSuffix := ""
diff --git a/patch/info/decl_info.go b/patch/info/decl_info.go
index 9eb03525..4cbce152 100644
--- a/patch/info/decl_info.go
+++ b/patch/info/decl_info.go
@@ -41,8 +41,10 @@ func (c DeclKind) String() string {
 }
 
 type DeclInfo struct {
-	FuncDecl  *syntax.FuncDecl
-	VarDecl   *syntax.VarDecl
+	FuncDecl *syntax.FuncDecl
+	VarDecl  *syntax.VarDecl
+
+	// when kind == CONST
 	ConstDecl *syntax.ConstDecl
 
 	// is this var decl follow a const __xgo_trap_xxx = 1?
diff --git a/patch/syntax/syntax.go b/patch/syntax/syntax.go
index 86c72cb1..22e94017 100644
--- a/patch/syntax/syntax.go
+++ b/patch/syntax/syntax.go
@@ -773,6 +773,18 @@ func generateFuncRegBody(pos syntax.Pos, funcDecls []*DeclInfo, xgoRegFunc strin
 			// there are function with name "_"
 			continue
 		}
+		// type unknown constant expr, will not be registered,
+		// see bug https://github.com/xhd2015/xgo/issues/53
+		// why not filter them earlier?
+		// because the node still needs to be marked, but effectively skipped
+		if funcDecl.Kind == info.Kind_Const && funcDecl.ConstDecl.Type == nil {
+			untypedConstType := getConstDeclValueType(funcDecl.ConstDecl.Values)
+			if untypedConstType == "" || untypedConstType == UNKNOWN_CONST_TYPE {
+				// exclude
+				continue
+			}
+		}
+
 		var fnRefName syntax.Expr
 		var varRefName syntax.Expr
 		if funcDecl.Kind.IsFunc() {
diff --git a/runtime/core/version.go b/runtime/core/version.go
index a4d3a5e7..2febb1fc 100644
--- a/runtime/core/version.go
+++ b/runtime/core/version.go
@@ -7,8 +7,8 @@ import (
 )
 
 const VERSION = "1.0.39"
-const REVISION = "55af407f826d020bcd28c51663d0879f8d1ca76e+1"
-const NUMBER = 258
+const REVISION = "4d63b2ed7ce161f17d1c311a9b536e82a01769f0+1"
+const NUMBER = 259
 
 // these fields will be filled by compiler
 const XGO_VERSION = ""
diff --git a/runtime/test/debug/debug_test.go b/runtime/test/debug/debug_test.go
index cf05eddb..56782591 100644
--- a/runtime/test/debug/debug_test.go
+++ b/runtime/test/debug/debug_test.go
@@ -12,18 +12,17 @@ import (
 	"testing"
 )
 
+const userNsLength = (1 << 16)
 const (
-	pod1 = "pod1"
+	minimumMappingUID = userNsLength
+	mappingLen        = userNsLength * 2000
 )
 
-type Pod struct {
-	Name string
-}
-
-func TestConstNameCollision(t *testing.T) {
-	var pod1 *Pod
+// see bug https://github.com/xhd2015/xgo/issues/176
+func TestUntypedUnknownConstShouldCompile(t *testing.T) {
+	var allocated uint32
 
-	if pod1 != nil && pod1.Name != "" {
-		t.Fatalf("pod1 should be empty")
+	if allocated > minimumMappingUID+mappingLen-userNsLength {
+		t.Fatalf("allocated is greater?")
 	}
 }
diff --git a/runtime/test/patch_const/patch_const_op_test.go b/runtime/test/patch_const/patch_const_op_test.go
index 511850cf..f61c13c2 100644
--- a/runtime/test/patch_const/patch_const_op_test.go
+++ b/runtime/test/patch_const/patch_const_op_test.go
@@ -1,6 +1,7 @@
 package patch_const
 
 import (
+	"fmt"
 	"testing"
 	"time"
 
@@ -10,9 +11,24 @@ import (
 const A = 20 * time.Second
 
 func TestPatchConstOp(t *testing.T) {
-	mock.PatchByName("github.com/xhd2015/xgo/runtime/test/patch_const", "A", func() time.Duration {
-		return 10 * time.Second
-	})
+	// patch should fail because registering were filtered
+	var errMsg string
+	func() {
+		defer func() {
+			if e := recover(); e != nil {
+				errMsg = fmt.Sprint(e)
+			}
+		}()
+		mock.PatchByName("github.com/xhd2015/xgo/runtime/test/patch_const", "A", func() time.Duration {
+			return 10 * time.Second
+		})
+	}()
+
+	expectErr := "failed to setup mock for: github.com/xhd2015/xgo/runtime/test/patch_const.A"
+	if errMsg != expectErr {
+		t.Fatalf("expect errMsg to be: %q, actual: %q", expectErr, errMsg)
+	}
+
 	a := A
 	if a != 20*time.Second {
 		t.Fatalf("expect patch A failed because current xgo does not resolve operation type, actual: a=%v, want: %v", a, 20*time.Second)
diff --git a/runtime/test/trap/trap_math_max_test.go b/runtime/test/trap/trap_math_max_test.go
new file mode 100644
index 00000000..9e6dd569
--- /dev/null
+++ b/runtime/test/trap/trap_math_max_test.go
@@ -0,0 +1,22 @@
+package trap
+
+import (
+	"math"
+	"testing"
+)
+
+// these should compile
+// see bug https://github.com/xhd2015/xgo/issues/53
+
+const SET_EMPTY_STRING = "<empty>"
+const SET_ZERO = math.MaxInt64 - 1
+const SET_ZERO_UINT = math.MaxUint64 - 1
+const SET_ZERO_INT32 = math.MaxInt32 - 1
+const SET_ZERO_UINT32 = math.MaxUint32 - 1
+
+func TestMathMaxShouldCompile(t *testing.T) {
+	zero := uint64(SET_ZERO_UINT)
+	if zero != math.MaxUint64-1 {
+		t.Fatalf("zero: %v", zero)
+	}
+}